/*
* This file is part of Project SkyFire https://www.projectskyfire.org.
* See LICENSE.md file for Copyright information
*/

#ifndef SF_WARDEN_BASE_H
#define SF_WARDEN_BASE_H

#include "ARC4.h"
#include "AuthDefines.h"
#include "ByteBuffer.h"
#include "WardenCheckMgr.h"
#include <array>

enum WardenOpcodes
{
    // Client->Server
    WARDEN_CMSG_MODULE_MISSING = 0,
    WARDEN_CMSG_MODULE_OK = 1,
    WARDEN_CMSG_CHEAT_CHECKS_RESULT = 2,
    WARDEN_CMSG_MEM_CHECKS_RESULT = 3,        // only sent if MEM_CHECK bytes doesn't match
    WARDEN_CMSG_HASH_RESULT = 4,
    WARDEN_CMSG_MODULE_FAILED = 5,        // this is sent when client failed to load uploaded module due to cache fail

    // Server->Client
    WARDEN_SMSG_MODULE_USE = 0,
    WARDEN_SMSG_MODULE_CACHE = 1,
    WARDEN_SMSG_CHEAT_CHECKS_REQUEST = 2,
    WARDEN_SMSG_MODULE_INITIALIZE = 3,
    WARDEN_SMSG_MEM_CHECKS_REQUEST = 4,        // byte len; while (!EOF) { byte unk(1); byte index(++); string module(can be 0); int offset; byte len; byte[] bytes_to_compare[len]; }
    WARDEN_SMSG_HASH_REQUEST = 5
};

enum WardenCheckType
{
    MEM_CHECK = 0xF3, // 243: byte moduleNameIndex + uint Offset + byte Len (check to ensure memory isn't modified)
    PAGE_CHECK_A = 0xB2, // 178: uint Seed + byte[20] SHA1 + uint Addr + byte Len (scans all pages for specified hash)
    PAGE_CHECK_B = 0xBF, // 191: uint Seed + byte[20] SHA1 + uint Addr + byte Len (scans only pages starts with MZ+PE headers for specified hash)
    MPQ_CHECK = 0x98, // 152: byte fileNameIndex (check to ensure MPQ file isn't modified)
    LUA_STR_CHECK = 0x8B, // 139: byte luaNameIndex (check to ensure LUA string isn't used)
    DRIVER_CHECK = 0x71, // 113: uint Seed + byte[20] SHA1 + byte driverNameIndex (check to ensure driver isn't loaded)
    TIMING_CHECK = 0x57, //  87: empty (check to ensure GetTickCount() isn't detoured)
    PROC_CHECK = 0x7E, // 126: uint Seed + byte[20] SHA1 + byte moluleNameIndex + byte procNameIndex + uint Offset + byte Len (check to ensure proc isn't detoured)
    MODULE_CHECK = 0xD9  // 217: uint Seed + byte[20] SHA1 (check to ensure module isn't injected)
};

#if defined(__GNUC__)
#pragma pack(1)
#else
#pragma pack(push, 1)
#endif

struct WardenModuleUse
{
    uint8 Command;
    uint8 ModuleId[16];
    uint8 ModuleKey[16];
    uint32 Size;
};

struct WardenModuleTransfer
{
    uint8 Command;
    uint16 DataSize;
    uint8 Data[500];
};

struct WardenHashRequest
{
    uint8 Command;
    uint8 Seed[16];
};

#if defined(__GNUC__)
#pragma pack()
#else
#pragma pack(pop)
#endif

struct ClientWardenModule
{
    uint8 Id[16];
    uint8 Key[16];
    uint32 CompressedSize;
    uint8* CompressedData;
};

class WorldSession;

class Warden
{
    friend class WardenWin;
    friend class WardenMac;

public:
    Warden();
    virtual ~Warden();

    virtual void Init(WorldSession* session, SessionKey const& k) = 0;
    virtual ClientWardenModule* GetModuleForClient() = 0;
    virtual void InitializeModule() = 0;
    virtual void RequestHash() = 0;
    virtual void HandleHashResult(ByteBuffer& buff) = 0;
    virtual void RequestData() = 0;
    virtual void HandleData(ByteBuffer& buff) = 0;

    void SendModuleToClient();
    void RequestModule();
    void Update();
    void DecryptData(uint8* buffer, uint32 length);
    void EncryptData(uint8* buffer, uint32 length);

    static bool IsValidCheckSum(uint32 checksum, const uint8* data, const uint16 length);
    static uint32 BuildChecksum(const uint8* data, uint32 length);

    // If no check is passed, the default action from config is executed
    std::string Penalty(WardenCheck* check = NULL);

private:
    WorldSession* _session;
    uint8 _inputKey[16] = { };
    uint8 _outputKey[16] = { };
    uint8 _seed[16] = { };
    SkyFire::Crypto::ARC4 _inputCrypto;
    SkyFire::Crypto::ARC4 _outputCrypto;
    uint32 _checkTimer;                          // Timer for sending check requests
    uint32 _clientResponseTimer;                 // Timer for client response delay
    bool _dataSent;
    uint32 _previousTimestamp;
    ClientWardenModule* _module;
    bool _initialized;
};

#endif
